For reasons of usefulness, coherence of content and timetable organisation, it is recommended that the enrolment of optional subjects should fully respect the structure of the proposed specialisations; in other words, whether one or the other is chosen, the two optional subjects included in each of them should be taken strictly. The optional subjects of one speciality must not be mixed with those of another.

If you choose the speciality of: Methods and techniques of analysis of the physical environment, the optional subjects to be taken together are:
41054. The Physical Environment. Fieldwork and cartography
41055. Restoration of the natural environment and analysis of climatic alterations.

If you prefer the other specialisation: Methods and techniques applied to spatial planning, the optional subjects to be taken are:
41056: Modelling techniques and geographic information systems.
41057: Qualitative and quantitative techniques for territorial planning and management.